Study ofB0→D*−π+π−π+andB0→D*−K+π−π+decays

Abstract

Using proton-proton collision data collected by the LHCb experiment at s=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1, the ratio of branching fractions of the B0→D*−π+π−π+ decay relative to the B0→D*−π+ decay is measured to be B(B0→D*−π+π−π+)B(B0→D*−π+)=2.64±0.04(stat)±0.13(syst). The Cabibbo-suppressed decay B0→D*−K+π−π+ is observed for the first time, and the measured ratio of branching fractions is B(B0→D*−K+π−π+)B(B0→D*−π+π−π+)=(6.47±0.37(stat)±0.35(syst))×10−2. A search for orbital excitations of charm mesons contributing to the B0→D*−π+π−π+ final state is also performed, and the first observation of the B0→D¯1(2420)0π+π− decay is reported with the ratio of branching fractions B(B0→(D¯1(2420)0→D*−π+)π−π+)B(B0→D*−π+π−π+)=(2.04±0.42(stat)±0.22(syst))×10−2, where the numerator represents a product of the branching fractions B(B0→D¯1(2420)0π−π+) and B(D¯1(2420)0→D*−π+).Received 2 April 2013DOI:https://doi.org/10.1103/PhysRevD.87.092001This article is available under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.© 2013 CERN, for the LHCb Collaboration